Thanks for the helpful advice although I don't think my post asked about the respective merits of FSNAV and FSBUILD but merely stated that I have both programs.However, there is still a matter I am unsure about and apologies in advance if your post has already answered my question:I have heard about SIDS/STARS, IAPS and now you mention transitions. In the PMDG FMC, I see SIDS mentioned on the DEP/ARR page but not IAP's. In FSNAV and FSBUILD, I see SIDS/STARS but not IAP's. Therefore, is it possible for a STAR to include the IAP and that is the reason I do not see IAP separately mentioned.Finally, is an IAP the same as a transition?If this is all too much to explain, perhaps someone could point me in the direction of some good literature I can read.ThanksRenzo Nicoletti